Monitoring sensors can transmit a multiplicity of operating data to the control of an escalator or a moving walkway in order to optimize the operation of these items of equipment for transport of persons and/or to increase the operating safety thereof.
In the case of known controls for escalators and moving walkways the drive is, for example, switched off when the escalator is unused or operated at reduced speed in an energy-saving mode termed ‘crawl travel’. When users approach the escalator then, for example, when passing through a light barrier or passing an infrared sensor a pulse is triggered and the drive switched on or the speed of the drive increased. After a predetermined period of time has elapsed, at the earliest after departure of the last user from the escalator, the drive is switched off again. The monitoring sensor necessary for that purpose is, as described in, for example, WO 98/18711 A1, accommodated in a column or post, which is arranged laterally of the access region, so as to be able to reliably detect the users.
EP 1 541 519 B1 discloses an arrangement of at least one radar monitoring sensor serving for detection of users approaching an escalator or a moving walkway. This monitoring sensor is concealed behind an opaque handrail entry cap so as not to be the target of vandalism.
The afore-described arrangements of monitoring sensors have the disadvantage that they are unable to monitor the entire access region. Due to the arrangement in a separate post or in the handrail entry cap of the passenger transport device areas of the respective access region to be monitored are necessarily not detected. In particular, the areas near the comb plate cannot be reached by the protection cone of the monitoring sensor, since parts of the balustrade or the balustrade base obstruct or interfere with detection. This can have the consequence that more elderly users who remain in these areas for a longer period of time are no longer recognizable for control of the escalator or the moving walkway and therefore a desired reaction of the control such as, for example, starting of the step belt or plate belt does not happen.